1. Field of the Invention
The invention pertains to the field of devices such as turnbuckles for tightening or taking up slack in chains, cables, ropes and the like.
2. Description of the Prior Art
In many applications, it is necessary to tighten or take up the slack in a chain, cable or rope particularly by drawing the two ends of the chain together around an object, or drawing together the ends of two chains whose ends are secured. Typically this has been done in the past by securing each end of the chain or cable or the ends of two chains or cables to the opposite ends of a turnbuckle and rotating the sleeve of the turnbuckle by hand. The amount of tensioning which can be accomplished by hand can be increased through the principle of the lever by inserting a bar or screwdriver through the opening in the turnbuckle and applying pressure at the end of the bar to rotate the sleeve. However, the amount of tension which can be applied in this manner is clearly limited.
For example, in a body shop environment, chains are commonly used to tie down the damaged vehicle while it is mounted on a stand and secure it so that work may be performed on the vehicle without the danger of the vehicle falling off the stand. At present, such chains are tightened using a turnbuckle but sufficient tension to maintain the vehicle in a rigid position cannot be obtained through hand-tightening of the turnbuckle. Similarly, loads on a truck or boat are often tied down using chains. In this application, load binders are often used to tighten the chain. These binders work on the principle of the lever and are locked in the closed position when the point of rotation passes through a point of highest tension into a rest position of slightly lower tension. This serves to retain the load binder in the closed position. However, because of the slight slackening involved in this locking method and because they are applied by hand, such binders cannot secure the chain under extreme tension.